Certain Freqs Input Same as Output?

[N5JMC]

I'm new so dont dog me. For my county in the business section, it has the outputs and when I select Show Input, it doenst have any. Is this because the input is different like HAM and they're just not in the database or do these particular freqs or businesses use the same freq for input as they do output. Here is a link to the page. Businesses Scanner Frequencies and Radio Frequency Reference

 

[rfradioconsult]

A lot of UHF systems may have two separate licenses with different call signs for the repeater (class FB2, FB6, etc.) and a separate license for the mobile stations (class MO).

 

[kma371]

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I'm new so dont dog me. For my county in the business section, it has the outputs and when I select Show Input, it doenst have any. Is this because the input is different like HAM and they're just not in the database or do these particular freqs or businesses use the same freq for input as they do output. Here is a link to the page. Businesses Scanner Frequencies and Radio Frequency Reference

It's because either the input isn't known or the frequency is simplex and doesn't have an input.

Most of the UHF ones are +5 though. Who ever entered it in the DB didn't include the input.

 

[SAR923]

Given the uses and freqencies shown on the linked page, it appears that the vast majority are simplex, so there wouldn't be an input frequency. The systems that are clearly repeated have an input frequency shown. It's easy enough to tell if a frequency is repeated by listening for the repeater drop out at the end of a transmission. If it's UHF, it's probably +5 on the input. If it's VHF, it could be almost any frequency, and either finding it in the FCC database or sitting on the system with close call is the only way to find it.

 

[N5JMC]

What do you mean finding it by sitting on the system with close call? Will I be able to hear them on my scanner on two frequencies close together and just know one is the input?

 

[captclint]

What do you mean finding it by sitting on the system with close call? Will I be able to hear them on my scanner on two frequencies close together and just know one is the input?

It depends on how close you are to the location of a mobile or sometimes the base(often, base stations use landline to a repeater). Close call is typically .1-.2 miles or less. If you are that close, you may hear only the mobile transmit freq, or only the base fransmit freq, but not at the same time. The freq may be the same as the base(simplex), or it could be different if repeated.

 

[SAR923]

As Clint said, sit somewhere near where one of those business frequencies is in use. If you think it's a repeater, use close call (or whatever the equivalent is on your scanner) to look for the input frequency. It's usually with a couple of megahertz up or down for VHF and +5 Mhz for UHF. If you hear the base and mobile on the same frequency with no repeater dropout squelch tone at the end of the transmission, then you know it's simplex.

 

[SkipSanders]

UHF Business stuff can not only be simplex or repeater, it can also be simplex on either the 'output' range of frequencies, or on the 'input' range of frequencies.

That is, 460-465 is 'output'. 465-470 is 'input'.

You will however find users licensed for simplex on both 464.6375 and 469. 2375, etc. You just have to look and see what the license shows, and listen to SEE how it's being used. Some systems also allow users to use simplex on the output of an otherwise repeated channel, for use when they're not in range of the repeater, or simply very close and don't want to be heard 'everywhere'.

 

[RKG]

UHF Business stuff can not only be simplex or repeater, it can also be simplex on either the 'output' range of frequencies, or on the 'input' range of frequencies.

Not so: absent a waiver, mobile-to-mobile communications on an "input" frequency is prohibited by Part 90.

 

[SkipSanders]

Sea World, San Diego. No base stations, no repeaters, all mobiles, simplex (actually handie talkies) On both 'input' and 'output' frequencies. This is common, as far as I can tell, for low power simplex business licensing of handie-talkie type systems.

ULS License - Industrial/Business Pool, Conventional License - KB41356 - Sea World of California - Frequencies Summary

ULS License - Industrial/Business Pool, Conventional License - KA90452 - Sea World of California - Frequencies Summary

------------
KA90452
000460.88750000 1 1 1 MO 100 2.000
000461.08750000 1 1 2 MO 100 2.000
000461.38750000 1 1 3 MO 100 2.000
000461.48750000 1 1 4 MO 100 2.000
000461.53750000 1 1 5 MO 100 2.000
000461.58750000 1 1 6 MO 100 2.000
000461.66250000 1 1 7 MO 100 2.000
000461.76250000 1 1 8 MO 100 2.000
000462.06250000 1 1 9 MO 100 2.000
000462.08750000 1 1 10 MO 100 2.000
000462.18750000 1 1 11 MO 100 2.000
000463.41250000 1 1 12 MO 100 2.000
000463.48750000 1 1 13 MO 100 2.000
000464.18750000 1 1 14 MO 100 2.000
000464.21250000 1 1 15 MO 100 2.000
000464.43750000 1 1 16 MO 100 2.000
000464.46250000 1 1 17 MO 100 2.000
000464.91250000 1 1 18 MO 100 2.000
000464.96250000 1 1 19 MO 100 2.000
000465.88750000 1 1 20 MO 100 2.000
000466.08750000 1 1 21 MO 100 2.000
000466.38750000 1 1 22 MO 100 2.000
000466.48750000 1 1 23 MO 100 2.000
000466.53750000 1 1 24 MO 100 2.000
000466.58750000 1 1 25 MO 100 2.000
000466.66250000 1 1 26 MO 100 2.000
000466.76250000 1 1 27 MO 100 2.000
000467.06250000 1 1 28 MO 100 2.000
000467.08750000 1 1 29 MO 100 2.000
000467.18750000 1 1 30 MO 100 2.000
000468.41250000 1 1 31 MO 100 2.000
000468.48750000 1 1 32 MO 100 2.000
000469.18750000 1 1 33 MO 100 2.000
000469.21250000 1 1 34 MO 100 2.000
000469.43750000 1 1 35 MO 100 2.000
000469.46250000 1 1 36 MO 100 2.000
000469.91250000 1 1 37 MO 100 2.000
000469.96250000 1 1 38 MO 100 2.000

KB41356
000461.16250000 1 1 1 MO 300 2.000
000461.68750000 1 1 2 MO 300 2.000
000461.78750000 1 1 3 MO 300 2.000
000462.88750000 1 1 4 MO 300 2.000
000463.66250000 1 1 5 MO 300 2.000
000463.68750000 1 1 6 MO 300 2.000
000463.71250000 1 1 7 MO 300 2.000
000466.16250000 1 1 8 MO 300 2.000
000466.68750000 1 1 9 MO 300 2.000
000466.78750000 1 1 10 MO 300 2.000
000467.88750000 1 1 11 MO 300 2.000
000468.66250000 1 1 12 MO 300 2.000
000468.68750000 1 1 13 MO 300 2.000
000468.71250000 1 1 14 MO 300 2.000

 

[menace3397]

Can someone please explain Simplex a bit more????

 

[SAR923]

Simplex just means that one radio talks directly to the other with no help from a relay station or repeater. This could be anything from two guys with HT's to a vehicle with a high powered mobile radio talking to a base station with a high powered radio. Might even have a landline or microwave link to a mountain top site but still be simplex, as long as the base and mobile talk to each other without any assistance from another radio, on another frequency, that repeats the traffic.

 

[Comint]

Can someone please explain Simplex a bit more????

Simplex just means Transmitting and Receiving on the same frequency.

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Comint